don't worry, i'm here to double check it for you. i don't think you're going to have much fun writing a C3 on a treble clef staff - you'd need an assload of ledger lines. it's pretty much to the point that it's not even practical to read.

my point, of course, being that your scientific pitch notation is an octave lower than it should be - middle C is C4, not C3 -- and the low range of a cello is C2 (as would be the concert pitch of the low C on a guitar), not C1.